CN117045947A

CN117045947A - Apparatus and method for metered dispensing of liquids

Info

Publication number: CN117045947A
Application number: CN202310381667.XA
Authority: CN
Inventors: S·沃格特; T·克卢格
Original assignee: Heraeus Medical GmbH
Current assignee: Heraeus Medical GmbH
Priority date: 2022-05-13
Filing date: 2023-04-11
Publication date: 2023-11-14
Also published as: EP4275714A1; US20230364335A1

Abstract

The present invention relates to a device and a method for metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body, and to the use of the device. An apparatus (10) for metered delivery of a liquid (12) for the purpose of releasing an active substance in a human or animal body comprises a metering device (14) for metering a defined volume of the liquid (12), an inlet (16) in fluid communication with the metering device (14) for supplying the liquid (12) to the metering device (14), and an outlet (18) in fluid communication with the metering device (14) for dispensing the defined volume of the liquid (12). The metering device (14) comprises a wall (21) surrounding a metering chamber (20) for receiving the liquid (12). By means of manual pressure on the wall (21), the metering chamber (20) can be reduced such that the defined volume of liquid (12) is delivered from the metering chamber (20) to the outlet (18).

Description

Apparatus and method for metered dispensing of liquids

The present invention relates to a device and a method for metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body, and to the use of the device.

The rheumatoid disease belongs to the so-called autoimmune disease, i.e. the immune system attacks the body's own structure, the cause of which is not clear. Rheumatoid arthritis and psoriatic arthritis belong to the group of rheumatic diseases and are associated with joint inflammation or arthritis, which is often chronic and can lead to progressive destruction of the joint. For systemic drug treatment of rheumatoid arthritis and psoriatic arthritis, a number of drug groups are available, such as analgesics, non-steroidal anti-inflammatory drugs, glucocorticoids and basic therapeutic agents (disease-modifying antirheumatic drugs, dMARD). In addition, there are modern antibodies (biologicals) that block alpha-TNF (alpha-tumor necrosis factor) or interleukin IL-17. However, with systemic medication, only relatively small serum concentrations of the active substance can be achieved, since otherwise undesired side effects, such as damage to the kidneys and liver, can occur. Higher serum concentrations are therefore generally avoided in practice.

As a result, the active substance concentration can only be very low at the target (e.g. in the joint capsule tissue and at the tendon stop), and thus only limited immunomodulatory effects are possible. Thus, in order to reduce the chronic inflammatory processes in the joint area of patients suffering from rheumatoid arthritis and psoriatic arthritis, as well as in many other diseases, it would be desirable if the corresponding active substances could be applied locally in the joint capsule and/or near the affected tendons or tendon stops, and in particular directly in the affected body structures, in order to achieve a locally high concentration of these active substances. Furthermore, a large number of additional clinical phenomena are known, in which only relatively low concentrations at the target site can be obtained by systemic administration of the active substance, even though higher local concentrations would be required.

In particular with respect to rheumatism, it would also be desirable for pain treatment, for local cytostatic release and for the treatment of neoplastic diseases if the affected patient himself could apply the active substance solution as required.

From publication EP3 978 065 A1, a medical fluid reservoir is known which can be implanted subcutaneously and filled by a cannula.

It is an object of the present invention to provide a device, a method and a use by means of which metered delivery of a liquid for the purpose of releasing an active substance in the human or animal body is possible and which obviate at least some of the above disadvantages. In particular, the patient should be enabled to release the active ingredient in person, if desired.

This object is achieved by a device according to claim 1 and a method and a use according to the independent claims. Advantageous embodiments are specified in the dependent claims.

In order to achieve this object, a device for metering the liquid for the purpose of releasing an active substance in the human or animal body is used. The apparatus includes a metering device for metering a defined volume of liquid, an inlet in fluid communication with the metering device for supplying liquid to the metering device, and an outlet in fluid communication with the metering device for dispensing the defined volume of liquid. The metering device includes a wall that encloses a metering chamber for receiving the liquid. By manual pressing on the wall, the metering chamber can be reduced such that the defined volume of the liquid is delivered from the metering chamber to the outlet.

The device is able to meter a defined volume of liquid by manual pressure and thus in a simple and reproducible manner. In this way a simple and safe release of the active substance is possible, in particular by the patient himself. The patient can personally determine the delivery time of the active substance solution.

Manual pressure may be applied by a finger. Manual pressure is applied to at least one region of the wall. The active substance solution may be supplied to the metering device through the inlet so that multiple or repeated releases of the active substance are possible. The outlet may be arranged in the vicinity of a designated site for active substance release, in particular in the patient. Likewise, a suitable conduit element may be disposed between the outlet and the designated location. Thus, the known drawbacks of high active ingredient concentrations can be achieved locally without having to accept high serum concentrations. Furthermore, due to its simple mechanical operation mode, the device is simple and durable, low in manufacturing costs and safe to use.

In one embodiment, the device is configured to be implanted under the skin (subcutaneous implantation). Alternatively or additionally, the device may be configured such that it may be attached to the skin, for example by adhesion.

The liquid comprises in particular at least one active substance. Liquid within the meaning of the present invention includes any type of solution with a liquid solvent.

The metering chamber is a chamber for metering. The metering chamber is reduced by manual pressure. This means that the internal volume of the metering chamber, in which liquid may be contained, is reduced. Thus, liquid is expelled from the metering chamber and reaches the outlet. In other words, the metering device is a manually operable mechanical pump. Manual pressure is applied to at least one region of the wall. In particular, the metering chamber may then be enlarged again and refilled with liquid, so that multiple metering is possible. Thus, liquid may flow into the metering chamber through the inlet and be discharged from the metering chamber in a metered manner through the outlet.

The metering chamber is sized such that it releases a defined volume of liquid under manual pressure on the wall. It cannot be excluded that the remaining volume remains in the metering chamber. Thus, the available volume does not necessarily correspond to the absolute volume of the metering chamber. By means of manual pressure, a defined volume of liquid is squeezed, in particular towards the outlet. In particular, the metering chamber is disk-shaped and/or has a circular shape in top view. In particular, the metering chamber has a flat underside and/or a convexly curved upper side. Accordingly, the shape of the metering chamber may be a plano-convex shape accordingly.

A defined volume of liquid is discharged from the outlet of the device. Delivery may occur directly within the patient. The device may also include one or more catheter elements into which the liquid is initially expelled and from which the liquid is then delivered into the patient. For example, the catheter element may be a tube. Delivery is particularly useful for purposeful introduction of fluids into an area of a patient's body, such as near joint capsule, tendon, and/or tendon dead center.

The inlet and outlet are openings that allow fluid communication with the metering chamber. There may be connection options for the conduit elements at the inlet and/or outlet. The device is adapted for metered dispensing of a liquid for the purpose of releasing an active substance in the human or animal body. The release of the active substance does not have to take place in the body, but can of course also take place on a specific body.

In one embodiment, at least one region of the wall is designed such that at least that region of the wall is elastically deformed by manual pressure. In other words, the wall is at least partially elastically deformable. In this way, the metering chamber can be reduced in a particularly simple and reliable manner. In particular, the wall of at least one side of the metering chamber is at least substantially composed of an elastically deformable material. In one embodiment, the wall of the entire metering chamber is partially or completely composed of an elastically deformable material. Thus, when the filling level of the metering chamber changes, the volume can be easily changed. In one embodiment, the wall of the metering chamber comprises a substantially rigid base plate and an elastic cover element mechanically connected to the base plate. The base plate and the cover element are in principle connected to each other in a liquid-tight manner.

In one embodiment, after the manual pressure ceases, the wall returns at least substantially to its original shape by an elastic restoring force. The elastic restoring force refers to a force by which the member or a portion thereof moves back to an original position or shape. The restoring force is in particular caused by the elasticity of the wall. The wall tries to return to its original shape. In this way, a negative pressure is generated in the metering chamber. When the external force ceases, the wall may return to its original shape. In particular, the liquid flows through the inlet into the metering chamber, preferably being sucked in by the negative pressure generated. This embodiment allows the metering chamber to be filled easily and metering to be performed reproducibly.

In one embodiment, the metering device includes a first check valve that prevents liquid from flowing from the metering chamber to the inlet and/or a second check valve that prevents liquid from flowing from the outlet to the metering chamber. A check valve is a component that allows liquid to flow in only one direction. The first check valve is typically designed and arranged such that it only allows liquid to flow through the inlet into the metering chamber. The second check valve is typically designed and arranged such that it only allows liquid to flow from the metering chamber to the outlet. This allows the metering chamber to be filled easily.

The first check valve may be designed as a ball valve, a flap valve and/or a Li Pu valve. The second check valve may be designed as a ball valve, a flap valve and/or a Li Pu valve. The movable body of the valve (such as the ball of a ball valve or the flap of a flap valve) may have a maximum extension or diameter of at most 1 mm. Valves of this type have proven to be durable and reliable in the current size range, non-reactive with active substances and low in production costs. In particular, a check valve may be inserted into the cavity of the housing of the provided device for this purpose. In particular, the check valve may be locked or screwed therein. For this purpose, the check valve has, in particular, on its outer side, a suitable profiled element for screwing or locking.

In one embodiment, the apparatus further comprises a supply chamber for receiving a supply of liquid to be metered. The supply chamber is in fluid communication with the inlet. The supply chamber is a chamber that serves as a supply. The supply chamber may be connected to the metering chamber or inlet via a conduit element.

In one embodiment, the supply chamber is fixedly connected to the inlet and/or the metering chamber. In this way, a particularly compact apparatus may be provided, which comprises both the supply means and the metering means. This is advantageous in particular when used as an implant. In one embodiment, the wall of the supply chamber comprises a substantially rigid base plate and an elastic cover element mechanically connected to the base plate. In one embodiment, at least a portion of the wall defining the supply chamber is integrally manufactured with at least a portion of the wall defining the metering chamber. For example, a common base plate and/or a common cover element are provided for the supply chamber and the metering chamber. In this way, the apparatus can be produced with little technical effort. For example, the cover element may be glued or welded to the housing or the base plate. In one embodiment, the metering chamber and the supply chamber are arranged adjacent to each other. Typically, the distance between the metering chamber and the supply chamber and/or the length of the conduit element arranged therebetween is at most 15mm, in particular at most 10mm, advantageously at most 5mm and preferably at most 3mm.

In particular, the volume of the supply chamber is at least 2 times, preferably 5 times, the volume of the metering chamber. In this way, multiple metering may be made possible without having to intermittently fill the supply chamber. In particular, the volume of the supply chamber is at most 50 times, typically 25 times and in one example 15 or 10 times the volume of the metering chamber. In contrast, an excessively large supply chamber is associated with an excessively large device, which creates a practical problem. The different orders of magnitude of this multiple arises from the very different volumes of the different active substances which are to be metered. Preferably, the metering chamber has an available volume of between 20 and 200 μl. However, smaller or larger volumes are also possible, depending on the active ingredient to be metered, the desired dosage and the active ingredient concentration in the liquid. In particular, the supply chamber has a volume of more than 50 μl, in particular 100 μl and preferably 200 μl and/or less than 20mL, in particular 10mL and preferably 5 mL. In particular, the details about the volume of the supply chamber relate to the available volume of the supply chamber, which corresponds to the maximum liquid volume of the supply chamber minus any liquid volume remaining in the supply chamber. The supply lumen typically has a maximum extension, e.g. a maximum diameter of 30 mm.

In particular, the supply chamber is disc-shaped and/or has a circular shape in plan view. In particular, the supply chamber has a flat underside and/or a convexly curved upper side. The shape of the supply chamber may be described as plano-convex.

In one embodiment, the supply chamber is formed by a wall that is elastically deformable at least in some areas such that the supply chamber decreases as the supply of liquid decreases. In this way, air or unwanted liquid is prevented from collecting in the supply chamber when the supply of liquid to be metered is reduced. Further, in this way, the supply chamber may be similar to and optionally manufactured with the metering chamber.

In particular, the wall of at least one side of the supply chamber is at least substantially composed of an elastically deformable material. In one embodiment, the wall of the entire supply chamber is partly or completely composed of an elastically deformable material. Thus, the volume can be easily changed when the filling level of the supply chamber is changed.

In one embodiment, the elastic restoring force of the metering chamber is greater than the elastic restoring force of the supply chamber. In particular, the elastic restoring force of the elastically deformable region of the wall of the metering chamber is greater than the elastic restoring force of the elastically deformable region of the wall of the supply chamber. In this way, it can be ensured that the at least partially reduced volume of the supply chamber increases again after metering or dispensing the liquid and thus aspirates the liquid from the metering chamber. In this way, it is particularly easy to pump liquid from the supply chamber into the metering chamber once metering has been completed, so that the liquid can then be metered again. This is accomplished without the need to apply pressure or external forces. This can be done also when the supply chamber or its walls need to be deformed.

At least a portion of the greater restoring force of the metering chamber may be achieved by a different material than the supply chamber. The wall and/or wall material of the metering chamber may have a greater elasticity, such as a smaller modulus of elasticity, than the wall or material of the supply chamber. The material of the wall of the metering chamber may have a greater hardness, for example a greater shore a hardness, than the material of the wall of the supply chamber. Preferably, the material of the metering chamber has a shore a hardness of greater than 60. The material of the supply chamber preferably has a shore a hardness of less than 60. In the case of different materials, the wall thickness may be the same or different. The differences mentioned may relate to a specific elastic portion of the wall of a specific cavity or the whole wall.

At least a part of the greater restoring force of the metering chamber may be achieved by a different wall thickness than the supply chamber. The wall thickness of the metering chamber may be greater than the wall thickness of the supply chamber. In the case of different wall thicknesses, the materials may be identical or different.

In one embodiment, at least one region of the wall of the supply lumen is designed such that a cannula (injection cannula) can pierce through at least this region of the wall of the supply lumen in order to introduce liquid into the supply lumen through the cannula.

In other words, at least one region of the wall is designed as a piercing region. In particular, the wall of at least one side of the supply lumen, in particular the wall of the entire supply lumen, is partly or completely made of a material that can be pierced by the cannula. The elastic region of the wall (e.g. the elastic cover element) is preferably designed as a piercing region. In this way, the supply can be filled in a simple manner without requiring a complicated opening of the cavity. This is particularly advantageous when used as an implant, wherein the cannula is guided through the skin layer and optionally through a fabric layer covering the implant. For example, the healthcare worker or the patient himself may fill the supply of liquid by means of a conventional injection cannula or a suitable pen. Thus, the device can be used for a long period of time without any implantation or removal of the device from the skin surface. When the injection cannula is withdrawn, the resulting perforation may close the wall, in particular due to the restoring force of the elastically deformable material.

In one embodiment, the device has a non-pierceable element to prevent unwanted piercing of the rear region of the wall. The rear region is the region opposite to the region of the wall to be pierced, or the rear region of the supply chamber. In particular, the non-pierceable element is arranged on the rear region of the wall. This refers in particular to the wall of the supply chamber. For example, the non-pierceable element is arranged on a substrate of the device. The non-pierceable element cannot be pierced by a manually operated injection cannula or by a pen. It stops the movement of the injection cannula. This reliably prevents penetration of the base of the supply lumen, damage to tissue located below the base, and damage to the device.

In one embodiment, the non-pierceable element is a non-pierceable plate. This allows protection against unnecessary puncturing with very little effort. In one embodiment, the non-pierceable element is made of a biocompatible material. In this way, interactions with the patient's body and with the liquid and active substances contained therein are prevented. The non-pierceable element is preferably made of metal. In particular, the non-pierceable element comprises or consists of titanium, a titanium alloy, tantalum, a tantalum alloy, silver, a silver alloy and/or stainless steel.

In one embodiment, the non-pierceable element is at least partially disposed in the supply lumen. By "at least partially in the supply chamber" is meant that at least a portion of the surface of the non-pierceable element is in contact with the liquid located in the supply chamber. This makes manufacturing very easy. In one embodiment, at least a portion of the surface of the non-pierceable element is coated with silver. Silver can have a preservative effect by releasing silver ions. Thus, the liquid located in the supply chamber may be protected from microbial contamination.

In one embodiment, the device comprises one or more conduit elements made of an elastically deformable material, in particular plastic, which are connected or connectable to the outlet. One or more catheter elements may be provided in a tube. Each conduit element has in particular an outer diameter of 3mm or less. In particular, at least one catheter element is implantable so as to be positioned in the body as close as possible to the intended release location.

In one embodiment, one or more of the catheter elements comprises perforations spaced apart from each other, wherein the perforations are in particular arranged along the longitudinal axis. When pressure is applied, each perforation is opened by the liquid located in the catheter element, so that the pressurized liquid leaves. Each perforation closes automatically after the end of the pressure application, in particular by the restoring force of the elastic material. According to the teachings of the unexamined patent application EP3795196A1 and/or EP3795196A1, the catheter element is preferably designed, in particular perforated. In an additional embodiment, a valve is arranged at the end of the one or more conduit elements, which valve reversibly opens when pressure is applied by the liquid and closes again after the end of the pressure application. In both of the above embodiments, there is no permanent opening in the catheter element. In this way, clogging, for example due to ingrowth of connective tissue or by blood permeation, is prevented. Thus, the catheter element may be used over a period of weeks to months.

In one embodiment, the device has a maximum height of less than 13mm, in particular less than 10 mm. Height refers to the total height of the body of the profiled element, which body comprises in particular the metering device, the inlet, the outlet and optionally the supply chamber. Irrespective of any conduit elements such as tubes connected to the outlet. Similarly, width and length refer to a particular overall dimension of the body. The maximum height is the height at the highest position. This applies similarly to the width and length. The highest position relates to a state of the device in which the supply chamber and/or the metering chamber are completely filled or filled as desired.

In other words, the device is flat. In this way, the device can be implanted particularly easily. The maximum height is preferably less than 7mm. The maximum height is typically greater than 4mm. In one embodiment, the device has a substantially flat underside. This may be provided by a substantially planar substrate. The substrate may be substantially rigid. In this way, the device can be implanted particularly easily. In particular, the device is disc-shaped.

In one embodiment, the width of the device is at least 3 times greater than the height of the device. In particular, the multiple is greater than 4 and/or less than 10, preferably less than 6. In each case, maximum width and maximum height are meant. In one embodiment, the length of the device is at least 5 times greater than the height of the device. In particular, the multiple is greater than 7 and/or less than 15, preferably less than 10. In each case, maximum length and maximum height are meant.

In one embodiment, the wall of the metering chamber is convex at least in some regions. The raised area is preferably the area of the wall to be manually pressed for pumping. In this way, the point to be pressed can be easily perceived. This is particularly advantageous when the device is used as an implant, as in this case it can be perceived through the skin.

During implantation, the device and optionally one or more catheter elements are arranged under the skin. In particular, a liquid filled device is implanted. This prevents air in the device that may be released during the first metering. The catheter element is typically positioned such that the active ingredient may be released at or near the designated site. For example, the device is implanted on the back of the hand so that liquid can be supplied to the rheumatic finger joints in a targeted manner.

Another aspect of the invention is a method for metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body using the device according to the invention. By manual pressing on the wall, the metering chamber is reduced such that a defined volume of liquid is delivered from the metering chamber to the outlet. All features, advantages and effects of the device mentioned at the outset also apply to the method and vice versa. In one embodiment, the device is implanted under the skin of a human or animal body. In an alternative embodiment, the device is fastened (in particular glued) to the skin surface. In one embodiment, the method is a therapeutic or non-therapeutic method. The liquid may comprise as active ingredient one or more of the group comprising: analgesics, non-steroidal anti-inflammatory drugs, glucocorticoids, basic therapeutic agents (disease modifying antirheumatic drugs, dMARD), biologies and immunomodulators, preferably those that are hydrolytically stable over a prolonged period of time.

An additional aspect of the invention is a method for filling a device according to the invention. The cannula pierces an area of a wall of the supply lumen to introduce liquid into the supply lumen through the cannula. All features, advantages and effects of the above aspects are also applicable to the method and vice versa.

A further aspect of the invention is the use of a device according to the invention for metered dispensing of a liquid for the purpose of releasing an active substance in the human or animal body. In particular, by manual pressing on the wall, the metering chamber is reduced such that a defined volume of liquid is delivered from the metering chamber to the outlet. In particular, the device is implanted under the skin of a human or animal body or is attached (in particular glued) to the skin surface. In one embodiment, the use is therapeutic or non-therapeutic. All features, advantages and effects of the above aspects are also applicable to the use and vice versa.

Exemplary embodiments of the present invention are also explained in more detail below with reference to the drawings. Features of the exemplary embodiments can be combined with claimed subject matter, either alone or in multiple, unless indicated otherwise. The claimed protection zones are not limited to the exemplary embodiments.

Showing:

fig. 1: according to a perspective view of the device of the present invention,

fig. 2: according to a plan view of the device of the invention,

fig. 3: a side view of an apparatus according to the invention;

fig. 4: a cross-sectional view of the device according to the invention when performing the method steps,

fig. 5: a cross-sectional view of the device according to the invention when carrying out additional method steps;

figure 6 is an enlarged detail from figure 5,

figure 7 is a perspective view of a device according to the invention,

FIG. 8 is a cross-sectional view of an apparatus according to the invention at the time of filling, and

fig. 9 is a cross-sectional view of the device according to the invention after filling.

Fig. 1 shows a device 10 for metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body. The apparatus 10 comprises a housing 37 in which the metering device 14 is housed. The metering device 14 comprises a metering chamber 20 delimited at the top by a resilient wall 21. By manual pressing with a finger 40 on the wall 21, a defined volume of liquid from the metering chamber 20 can be output from the outlet 18 of the device. A conduit element (i.e. tube 35) is connected to the outlet 18, through which conduit element the metered volume can be guided to the target location.

As an inlet, the metering chamber 20 comprises a fluid connection to a supply chamber 22, which is likewise accommodated in a housing 37. The supply chamber 22 is also delimited upwardly by a flexible wall 23. Thus, after the liquid has been metered, the liquid may flow from the supply chamber 22 into the metering chamber 20 to allow for re-metering.

Fig. 2 shows a plan view, and fig. 3 shows a side view. It can be seen that the width B and length L of the device 10 are both significantly greater than the height H of the device 10. The width B of the device 10 is 5 to 6 times greater than the height H of the device. The length L of the device 10 is 8 to 9 times greater than the height H of the device. The height H of the device is between 5mm and 7mm. Generally, the device 10 is flat, plate-like and compact so as to allow implantation under the skin of a patient. In particular, the available volume of the supply chamber 22 is 6 to 10 times greater than the available volume of the metering chamber 20, so that 6 to 10 dose operations are possible.

Fig. 4 and 5 show possible layouts and uses of the device 10 in longitudinal section. A metering device 14 having a metering chamber 20 and an inlet 16 and an outlet 18 is shown. A supply chamber 22 is connected to the inlet 16. A pipe connection 34 and a pipe 35 connected thereto are located at the outlet 18. The first check valve 31 allows liquid to flow from the supply chamber 22 through the inlet 16 into the metering chamber 20, but not in the opposite direction. The second check valve 32 allows liquid to flow from the metering chamber 20 to the outlet 18 but not in the opposite direction. This ensures that the flow direction of the liquid is always as expected. The penetration of the metered liquid or body fluid into the device is prevented.

The housing 37 of the device comprises a base plate 38, an outer and a central upper housing part. The housing 37 is made of a relatively hard plastic material. The upper regions of the wall 21 of the metering chamber 20 and the wall 23 of the supply chamber 22 fastened to the housing 37 are made of an elastic material and can be deformed accordingly.

The elastic wall 23 of the supply chamber 22 is designed such that it can be pierced by a cannula in order to introduce the liquid 12 into the supply chamber 22. This is shown in fig. 7 to 9, which will be discussed below. The device 10 further comprises a non-pierceable element 25 which prevents undesired piercing of the substrate 38. The non-pierceable element 25 is formed as a non-pierceable plate 26 made of a biocompatible metal material, which is arranged on the upper side of the base plate 38 in the interior of the supply chamber 22. The device can thus be shown in X-rays. The upper side of the non-pierceable plate 26 is preferably coated with silver.

Fig. 4 shows a state in which both the metering chamber 20 and the supply chamber 22 are filled with the liquid 12. The specific flexible walls 21 and 23 are each convexly curved upward. This makes it possible to feel the metering chamber 20 and thus the point at which the manual pressure is to be applied very easily.

Fig. 5 shows a subsequent state in which the liquid 12 is expelled through the outlet 18, the tube connection 34 and the tube 35 by manually pressing a finger 40 onto the wall 21 of the metering chamber 20. The first check valve 31 is blocked so that no liquid can flow from the metering chamber 20 into the supply chamber 22. In contrast, the second check valve 32 opens so that liquid may pass from the metering chamber 20 to the outlet 18.

On the one hand, the convex curvature of the metering chamber 20 in fig. 5 and thus its volume is reduced compared to fig. 4. This may be continued by pressing the finger 40 further down until the end point is reached, for example when the wall 21 contacts the substrate 38 at least in the middle. In other words, the metering chamber 20 is reduced to transfer a defined volume of liquid 12 from the metering chamber 20 to the outlet 18. In this case, a defined volume of liquid 12 is then metered. On the other hand, the convex curvature of the supply chamber 22 and thus its volume is also reduced. This may be the case, for example, because one or more dosing operations have been performed in advance.

After the metering has been performed, the finger 40 may be removed. Due to the elastic restoring force of the wall 21, a negative pressure is generated in the metering chamber 20, which causes the first check valve 31 to open. In this way, liquid 12 may flow from the supply chamber 22 into the metering chamber 20. In this way, the wall 23 of the supply chamber 22 is deformable.

Fig. 6 shows an enlarged detail of fig. 5. The valve body 33 of the first check valve can be seen in its closed position. It is pressed to the left against the valve housing by the force of a compression spring arranged on the right in the valve and, if applicable, additionally by the pressure of the liquid 12 in the metering chamber 20 and thus blocks the flow through the valve. In contrast, the valve body 33 of the second check valve 32 is in the open position. Due to the pressure of the liquid 12 in the interior of the metering chamber 20, the valve body 33 is pressed to the right against the force of a pressure spring arranged to the right in the valve, so that a gap is created between the valve body 33 and the valve housing on the left, through which gap the liquid 12 can flow through the valve body 33 and out through the outlet 18.

Fig. 7 shows the device 10 according to the invention before filling the supply chamber 22 with liquid. A pen 28 having a cannula 29 is disposed directly over the pierceable region 24 of the wall 23 of the delivery lumen 22. Fig. 8 shows the cannula having pierced through wall 23 into supply lumen 22. The non-pierceable plate 26 prevents unwanted piercing of the area opposite the wall 23 (in this case the base plate 38). Liquid 12 is shown flowing out of pen 28 through cannula 29 into supply chamber 22. Due to the restoring force of the spring in the first check valve 31, the valve remains closed and liquid does not flow into the metering chamber 20.

Fig. 8 shows a subsequent step in which the supply chamber 22 is completely filled and the pen 28 with cannula 29 has been pulled out of the wall 23. The wall 23 of the supply chamber 22 is slightly curved upwards. As an alternative to the illustration shown here, the filling can also take place in such a way that the metering chamber 20 is also filled with liquid 12. For this purpose, the liquid 12 must exert a pressure in the supply chamber 22 in order for the first check valve 31 to open. Preferably, the spring force in the second check valve 32 is then greater so that accidental outflow of liquid through the second check valve 32 is prevented.

List of reference numerals

Apparatus 10

Liquid 12

Metering device 14

Inlet 16

Outlet 18

Metering chamber 20

Wall 21

Supply chamber 22

Wall 23

Region 24

Non-pierceable element 25

Non-pierceable plate 26

Pen 28

Cannula 29

First check valve 31

Second check valve 32

Valve body 33

Height H

Width B

Length L

Pipe connection 34

Tube 35

Housing 37

Bottom plate 38

Finger 40

Claims

1. An apparatus (10) for metered delivery of a liquid (12) for the purpose of releasing an active substance in a human or animal body, comprising a metering device (14) for metering a defined volume of the liquid (12), an inlet (16) in fluid communication with the metering device (14) for supplying the liquid (12) to the metering device (14), and an outlet (18) in fluid communication with the metering device (14) for delivering the defined volume of the liquid (12), wherein the metering device (14) comprises a wall (21) enclosing a metering chamber (20) for receiving the liquid (12), characterized in that the metering chamber (20) is reducible by manual pressure on the wall (21) such that the defined volume of the liquid (12) is transferred from the metering chamber (20) to the outlet (18).

2. The device (10) according to claim 1, characterized in that the wall (21) is designed such that at least one region of the wall (21) is elastically deformed by the manual pressure and the wall (21) returns at least substantially to its original shape by an elastic restoring force after the manual pressure has stopped.

3. The apparatus (10) according to one of the preceding claims, wherein the metering device (14) comprises a first check valve (31) preventing the liquid (12) from flowing from the metering chamber (20) to the inlet (16), and a second check valve (32) preventing the liquid (12) from flowing from the outlet (18) to the metering chamber (20).

4. The device (10) according to one of the preceding claims, characterized in that the device (10) further comprises a supply chamber (22) for receiving a supply of the liquid (12) to be metered, wherein the supply chamber (22) is in fluid communication with the inlet (16), wherein the volume of the supply chamber (22) is larger than the volume of the metering chamber (20), in particular at least 2 times, preferably 5 times, thereof.

5. The device (10) according to the preceding claim, characterized in that the supply chamber (22) is formed by a wall (23) which is elastically deformable at least in some areas such that the supply chamber (22) decreases with a decrease in the supply of the liquid (12).

6. The device (10) according to the preceding claim and claim 2, wherein the elastic restoring force of the metering chamber (20) is greater than the elastic restoring force of the supply chamber (22).

7. The device (10) according to one of the three preceding claims, characterized in that at least one region (24) of the wall (23) of the supply chamber (22) is designed such that a cannula (29) can pierce through the wall (23) of the supply chamber (22) in order to introduce liquid (12) into the supply chamber (22) through the cannula (29).

8. Device (10) according to the preceding claim, characterized in that the device (10) has a non-pierceable element (25) such that undesired piercing of the rear region of the wall (23) of the supply chamber (22) is prevented.

9. Device (10) according to the preceding claim, characterized in that said non-pierceable element (25) is a non-pierceable plate (26) made of biocompatible material, said non-pierceable plate being at least partially arranged in said supply chamber (22).

10. The device (10) according to one of the preceding claims, characterized in that the device (10) has a maximum height (H) of less than 13mm, in particular less than 10 mm.

11. The device (10) according to one of the preceding claims, characterized in that the width (B) of the device (10) is at least 3 times the height (H) of the device (10) and/or the length (L) of the device (10) is at least 5 times the height (H) of the device (10).

12. The device (10) according to one of the preceding claims, characterized in that the wall (21) of the metering chamber (20) is convex at least in some regions.

13. Method for metered delivery of a liquid (12) for the purpose of releasing an active substance in a human or animal body using a device (10) according to one of claims 1 to 12, wherein the metering chamber (20) is reduced by manual pressure on the wall (21) such that a defined volume of the liquid (12) is delivered from the metering chamber (20) to the outlet (18).

14. The method according to the preceding claim, characterized in that the device (10) is implanted under the skin of a human or animal body.

15. Use of a device (10) according to one of claims 1 to 12 for metered delivery of a liquid (12) for the purpose of releasing an active substance in a human or animal body, wherein the device (10) is implanted under the skin, in particular in a human or animal body.